The internal tubs of dishwashers typically have a generally rectangular or square shape. For example, the width of the opening of the tub, where dishes may enter and be removed from the tub through the use of a dishwasher tray, may have the same or different size than the length of the tub from the front to the back of the tub. Further, the front portion and rear sidewall of the tub may be generally perpendicular to the other sidewalls of the tub. However, despite these generally rectangular or square configurations, wash systems typically spray water inside the tub in a circular pattern.
For example, typical dishwasher systems have a rotating spray arm that is propelled by water pressure. When dishes and utensils are being washed in the tub, water pressure propels the spray arm in a circular pattern to spray water and detergent onto as many surfaces of the dishes and utensils as possible. However, as the spray arm moves in a circular pattern, the water delivered by the spray typically cannot reach the corners of the tub, or does not reach the corners, or corner areas, in desired quantities and/or regularity. Thus, dishes placed in the far corners of the tub may receive a smaller amount of water and/or detergent exposure, and therefore may not be washed as well or as thoroughly as dishes and utensils in other areas of the tub that are more adjacent to the spray arm.
Further, as a moving part, the tub should be designed to utilize at least a portion of the space in the tub to accommodate the rotational movement of the spray arm. Moreover, in order for the spray arm to operate, dishes and/or other items in the tub must not be in a position that may interfere with the movement of the spray arm. Thus, the need to dedicate at least a portion of the space in the tub to the movement of the spray arm may reduce the space available for cleaning dishes or other items. Further, such reduction in space may require that taller dishware and other similar tall items be oriented differently in the dishwasher, such as being laid to a side, which may result that dishware occupying additional space in the dishwasher tray so as to reduce the number of other items that may be loaded in the dishwasher tray. Yet, a reduction in the number of items that may be placed in the dishwasher tray may increase overall water and energy usage, as smaller loads of dishes and items being washed may result in an increase in the frequency that the dishwasher is operated.